Core insulator



Dec. 7,1948. 1; P. YOUNG 2,455,720

CORE INSULA'IOR Filed Jafi. 15, 1947 lllllfllllllll INVENTQR g5 15 Zeozzard]? Young.

BY i

ATTORNEY Patented Dec. 7, 1948 UNITED STATES PATENT OFFICE CORE INSULATOR Leonard P. Young, Chester, Conn.

Application January 15, 1947, Serial No. 722,134

6 Claims. (Cl. 201-63) This invention relates generally to electric heating devices employing resistance wires, and especially to an insulator for the termini of such wire.

As is well known in the art, the association-of the heating element ends in electric soldering irons with the cord extending from the handle of the iron usually presents difliculties in the assembly, and problems in the use of the iron, resulting in failures and repairs. When round resistance wire is employed the difliculty of connecting the ends thereof to suitable leads is not as great as in the case of ribbon resistance wire, which latter, while frail, and therefore more difficult-to handle, is nevertheless preferred because of its flatness.

The present invention has for its prime object the provision with the support for a heating element of an insulator structure which will not only readily facilitate the association of the ends of a flat resistance wire with sturdy leads connected to the electric cord, but which also provides the necessary protection against breakage of the resistance wire, and especially of its bare end portions extending from the coil formation on the support toward the connecting points with such leads.

A more specific object of the present invention is to provide an insulator structure wherein are employed two cooperating insulator members consisting of lower and upper portions, which, when in their engagin position are adapted to form protective guide channels for the reception of the bare ends of the resistance wire, and suitable through-passages for bringing the wire ends to a position at which they may be secured to the leads at points at the exterior of the. insulating structure.

Another object of this invention is the pro-,

vision in the aforestated insulator structure, of ducts for anchoring therein suitable wire leads in such a relation to the resistance wire, whereby the attachment of the latters termini to the leads is best facilitated, and whereby any strain upon the resistance wire ends is effectively absorbed by the anchored leads.

The foregoing and numerous other objects and advantages of the present invention will become more fully evident from the ensuing description in conjunction with the accompanying drawings, which latter, while showing a specific construction of the present invention, are by no means intended to limit the same to the actual showing, and wherein:

Fig. 1 is a fragmental perspective view of a heating element including the insulator of the instant development;

- Fig. 2 is an enlarged side elevation of Fig. 1, partially in vertical section;

Fig. 3 is a top view of the upper insulating member;

Fig. 4 is a side view thereof;

Fig. 5 is an end view thereof;

Fig. 6 is a bottom view of the upper insulating member;

Fig. 7 is a top view of the lower insulating member;

Fig. 8 is a side view thereof; and

Fig. 9 is an end view thereof.

Referring now specifically to the figures, numeral l0 denotes a resistance coil structure consisting of a core or element support ll, provided with a transverse recess l2 and a flanged end l3. Secured within the recess is an insulating structure [4 consisting of a lower member l5, which is wholly imbedded within recess l2, and an upper member IS, the lower end of which partially extends "into the recess. It sometimes becomes advisable to impinge the upper member within the recess by indentations or punch marks shown at H in Fig. 1, although such punch marks are not essential. I

The upper portion or member I6 of the insulating structure comprises a block formation with two parallel sides l8, and vertical ends l8, the upper portions of which ends change into beveled faces [9 to reduce the top end of member l6 and thus facilitate the insertion and setting of the resistance structure into the outer casing of an electric instrumentality. At the lower end of the block formation there is provided an endwisely reduced bottom extension 20 having a recess 2| extending over the latters entire length. In the body of the block are provided two pairs of through-passages, one pair 22 of which, arranged in the longitudinal vertical center plane of the block, being parallel with one another, and also being parallel with the vertical center axis passing through the block. The bottom ends of passages 22 terminate in enlargements 23, which issue into recess 2|. The other pair of passages 24 are inclined and are arranged symmetrically to one another and are disposed in near proximity to side faces 18 0f the block. Their upper ends are in alignment with the upper ends of apertures 22, while their lower ends issue at diagonally opposite points and at the ends of recess 2!.

The lower portion or lower member l5 comprises an elongated, rather flat formation pro vided with rounded ends 25, and from its upper surface there extends centrally and longitudinally between the two rounded ends a rib 26. The length of the lower insulating member substantially corresponds to the length of extension 20 of the upper member, and the height of rib 26 of the lower member substantially corresponds to the depth of recess 2| in extension 20. The Width of rib 26 is substantially less than the width of recess 2|, however the rib is sufficiently wide to cover the enlarged ends 23 of passages 22 when the two members are placed in engagement with one another, as clearly indicated in Fig. 5. In that position rib 26 divides recess 2| longitudinally into two parallel channels 21. These channels attain importance from the standpoint of efiicient assembly of electric heating instrumen talities, such as electric soldering irons.

Referring now to Fig. 2, core or support P2 is covered with an insulating layer around which iswound a fiat resistance wire 28. One end 29 of this resistance wire passesfrom the end of one of the channels 21 to its opposite end and from there is directed through the right hand throughpassage- 24 to without block F6. The other end 30 of the resistance wire enters the right hand end of the other channel, passes through the channel to its left end, and thence is directed to the left hand passage 24 to' without the insulator body. Within the two parallel passages 22 there are secured lead Wires 3| which are provided with enlargements 32 anchored in enlarged portions 23 of pass-ages'2'2, Ends 29 and 30 of the heating element are secured to leads 3| exteriorly to the insulator structure.

It willbe observed that channels 27, which extend across the coreor element support, are so arrangedthat the ends 29 and 30 of the heating' "element may be readily directed through them'into through-passages 24 without straining them, and that all the strain upon these element ends is taken up by anchoredlead wires 31. It will be also observed that the element ends run flatl ythrough channels 27 and passages 24 without twisting on -their way to being attached to lead wires 3|; In heretofore'd'evices an inadvertent twist in fiat resistance wire elements usually causes a break requiring replacement, often ofthe entire'element.

Qne of the-advantages of reducing the bottomportion of the upper member and making the lower member of the same length as the reduced extension of the upper member, resides in the fact that no port-ions of the heatingelement are exposed or are broughtso near'tothe 'out'er-"sun face of thecore that they may be subject to damage in assembly,

While, as previously stated, only one embodiment -of the present invention is illustrat'ed'and described, changes and improvements in its structure-may be required in order to adapt the same for-various purposes, and which changesand im'-- provementsare-to be considered to lay within the scope of the invention, as defined in-the annexedclaims.

I claim:

1. In arr insulator for resistance wireof electric soldering irons or the like, a substantially narrow, elongated and relatively high two-piece structure adapted for association with the re-- cessed end of a casing for supporting a heating element, said' two-piece 'structurecomprising upper and lower cooperating portions; said upperportion having an endwisely reduced downward extension provided with a recess along its entire length, a pair of vertical, parallel lead passages transversing the body of said upper portion and having enlarged ends terminating in the recess, and a pair of inclined, resistance wire-receiving passages extending from the top of the upper portion into and terminating at the ends of the recess; said lower portion having an upwardly directed, centrally disposed rib extending along its entire length, said rib being adapted to project into said recess, whereby the latter is divided' into two parallel channels, and to seal the enlarged ends of said lead passages.

2. In an insulator for the purpose indicated, a two-piece dielectric structure composed of upper and lower cooperating portions, the upper portion forming an elongated block with substantially parallel sidesand tapering upper ends and having an endwisely reduced bottom extension provided with a recess along its full length, a plurality of through-passages in the body of the upper portion, for the' reception of leads and resistance Wire, all: terminating in said recess; said lower portion" forming a body with rounded ends and having an upwardly directed, centrally disposed rib formation extending from end to end and directed into said recess, said rib formation being adapted to'sealthe bottom ends of the throughpassages for the leads and to divide the recess of the upper portion into two parallel channels for guiding. and insulating the ends of a resistance element.

3. In an insulator for leads and the ends of a resistance. element, the combination with a .resistance element support having a substantially channel-shaped recess in its flanged end, of an insulator structure placed in said recess, said structure comprisin cooperating upper and lower interengagedportions forming guide channels for receiving, separating and guiding the ends of a resistance element, the upper portion having a plurality of means for accommodating and anchoring lead wires and for facilitating their connectionwith the ends of a resistance element.

4'. In an electric heating device, an element support having a flanged end and a recess in said end;.a heating element wound about the support, an insulator structure held in said support recess and comprising' upper and lower portions, the latter. portionsubstantially filling said recess, the majorpart of the upper portion extending beyond the recess, guide channels for the ends of the heating element formed by the tWo insulator porti'on's within the recess of the element support, a plurality of through-passages in the upper portion, onepai'r of these through-passages having enlarged ends, lead wires with enlarged ends anchored in that one pair of passages, another pair of passages terminating in said guide channels, the ends of the heating element passing through said channels and into said other pair of passages and being secured 'to'said lead wires withoutthe body of the upperp'ortion of the insulatorstructure.

In ane'lectric heating device,- the combination with the support for a resistance coil, of an insulator for the resistance wire secured at one end of thesupport and comprising cooperating lower and upper members, the lower member tworesistance wireends formed between the" twomernbersand extending across the body of the support, said upper member havin ga set of parallel-passages with enlarged'ends, and another set of inclined passages terminating at the channel ends, lead wires anchored in-the parallel passages, and the ends of the resistance wire passing from the channels through the inclined passages into engagement with the lead wires.

6. An insulator for an electric heating device, comprising cooperating lower and upper members, adapted, when in engagement with each other, to form guide channels for a resistance wire or the like, the lower member having an elongated body portion with rounded ends, a rib extending from the body portion centrally between its ends, the upper member constitutin a block with a depending extension, the latter substantially corresponding in length to that of the lower member, a longitudinal recess provided in' said extension, the depth of said recess corresponding substantially to the height of the rib of the lower member, the width of the recess being REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date Kuhn et al Aug. 15, 1922 Number 

